Memory cell arrays

ABSTRACT

The invention includes a method of forming an array of memory cells. A series of capacitor constructions is formed, with the individual capacitor constructions having storage nodes. The capacitor constructions are defined to include a first set of capacitor constructions and a second set of capacitor constructions. A series of electrically conductive transistor gates are formed over the capacitor constructions and in electrical connection with the capacitor constructions. The transistor gates are defined to include a first set that is in electrical connection with the storage nodes of the first set of capacitor constructions, and a second set that is in electrical connection with the storage nodes of the second set of capacitor constructions. A first conductive line is formed over the transistor gates and in electrical connection with the first set of transistor gates, and a second conductive line is formed over the first conductive line and in electrical connection with the second set of transistor gates. The invention also includes an array of memory cells.

CROSS REFERENCE TO RELATED APPLICATION

This patent is a divisional of U.S. patent application Ser. No.10/632,272, filed Jul. 31, 2003, entitled “Methods of Forming MemoryCells, And Memory Cell Arrays”, now U.S. Pat. No. 7,005,692, which is acontinuation of U.S. patent application Ser. No. 10/368,978, filed onFeb. 18, 2003, entitled “Methods of Forming Memory Cell Arrays”, nowU.S. Pat. No. 6,958,268, which is a divisional of U.S. patentapplication Ser. No. 10/017,542 filed on Dec. 13, 2001, entitled“Methods of Forming Memory Cells, And Memory Cell Arrays”, now U.S. Pat.No. 6,593,610 B2, issued Jun. 15, 2003; the entirety of all of which areincorporated by reference herein.

TECHNICAL FIELD

The invention pertains to memory arrays and methods of forming memorycells. In particular applications, the invention pertains to methods offorming dynamic random access memory (DRAM) arrays.

BACKGROUND OF THE INVENTION

A continuing goal in semiconductor processing is to reduce the amount ofsemiconductor wafer real estate consumed by integrated circuit devices.Exemplary integrated circuit devices are memory devices, such as, forexample, DRAM devices. The DRAM devices are typically provided inarrays, with individual memory units comprising a transistor and acapacitor. Each individual DRAM unit of the array is provided with aunique address, which enables the individual units to be separatelyaccessible relative to one another for reading and writing memory bits.It would be desirable to develop novel constructions of DRAM deviceswhich reduce an amount of semiconductor real estate associated with thedevices.

SUMMARY OF THE INVENTION

In one aspect, the invention encompasses a method of forming an array ofmemory cells. A series of capacitor constructions is formed, with theindividual capacitor constructions having storage nodes. The capacitorconstructions are defined to include a first set of capacitorconstructions and a second set of capacitor constructions. A series ofelectrically conductive transistor gates are formed over the capacitorconstructions and in electrical connection with the capacitorconstructions. The transistor gates are defined to include a first setthat is in electrical connection with the storage nodes of the first setof capacitor constructions, and a second set that is in electricalconnection with the storage nodes of the second set of capacitorconstructions. A first conductive line is formed over the transistorgates and in electrical connection with the first set of transistorgates, and a second conductive line is formed over the first conductiveline and in electrical connection with the second set of transistorgates.

In another aspect, the invention encompasses an array of memory cells.The array includes a series of capacitor constructions, with thecapacitor constructions being defined to include a first set and asecond set. A conductive material is over the capacitor constructions,and in electrical connection with storage nodes of the capacitorconstructions. A first conductive line is formed over the conductivematerial and in electrical connection with the first set of capacitorconstructions through the conductive material. A second conductive lineis over the first conductive line and in electrical connection with thesecond set of capacitor constructions through the conductive material.The second conductive line is electrically connected with the conductivematerial through conductive interconnects extending within openings inthe first conductive line.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred embodiments of the invention are described below withreference to the following accompanying drawings.

FIG. 1 is a diagrammatic, cross-sectional, fragmentary view of a pair ofportions of a semiconductive wafer shown at a preliminary processingstep in accordance with a method of the present invention.

FIG. 2 is a view of the FIG. 1 portions shown at a processing stepsubsequent to that of FIG. 1.

FIG. 3 is a view of the FIG. 1 portions shown at a processing stepsubsequent to that of FIG. 2.

FIG. 4 is a view of the FIG. 1 portions shown at a processing stepsubsequent to that of FIG. 3.

FIG. 5 is a view of the FIG. 1 portions shown at a processing stepsubsequent to that of FIG. 4.

FIG. 6 is a view of the FIG. 1 portions shown at a processing stepsubsequent to that of FIG. 5.

FIG. 7 is a view of the FIG. 1 portions shown at a processing stepsubsequent to that of FIG. 6.

FIG. 8 is a view of the FIG. 1 portions shown at a processing stepsubsequent to that of FIG. 7.

FIG. 9 is a view of the FIG. 1 portions shown at a processing stepsubsequent to that of FIG. 8.

FIG. 10 is a view of the FIG. 1 portions shown at a processing stepsubsequent to that of FIG. 9.

FIG. 11 is a view of the FIG. 1 portions shown at a processing stepsubsequent to that of FIG. 10.

FIG. 12 is a view of the FIG. 1 portions shown at a processing stepsubsequent to that of FIG. 11.

FIG. 13 is a view of the FIG. 1 portions shown at a processing stepsubsequent to that of FIG. 12.

FIG. 14 is a view of the FIG. 1 portions shown at a processing stepsubsequent to that of FIG. 13.

FIG. 15 is a view of the FIG. 1 portions shown at a processing stepsubsequent to that of FIG. 14.

FIG. 16 is an alternate view of the portions of FIG. 15,diagrammatically illustrating electrical connections associated withillustrated electrical devices.

FIG. 17 is a diagrammatic, schematic, top view of a semiconductor waferfragment illustrating a relative orientation of conductive lines formedin accordance with methodology of the present invention.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

An exemplary method of the present invention is described with referenceto FIGS. 1-17. Referring initially to FIG. 1, a semiconductor wafer 10is illustrated in fragmentary view, and specifically, a pair offragmentary portions 12 and 14 of the wafer fragment 10 are illustrated.Portions 12 and 14 are ultimately to comprise part of a memory array,and in the described aspect of the invention will ultimately comprisepart of a DRAM array. For purposes of the discussion that follows,portion 12 can be referred to as a first portion (or region) of thesemiconductor wafer 10, and portion 14 can be referred to as a secondportion (or region) of the wafer.

Portions 12 and 14 comprise a substrate 16. Substrate 16 can comprise,for example, a monocrystalline silicon wafer lightly doped with abackground p-type dopant and/or an n-type dopant. To aid ininterpretation of the claims that follow, the terms “semiconductivesubstrate” and “semiconductor substrate” are defined to mean anyconstruction comprising semiconductive material, including, but notlimited to, bulk semiconductive materials such as a semiconductive wafer(either alone or in assemblies comprising other materials thereon), andsemiconductive material layers (either alone or in assemblies comprisingother materials). The term “substrate” refers to any supportingstructure, including, but not limited to, the semiconductive substratesdescribed above.

Substrate 16 further comprises a damage region 18 formed therein, andrepresented by a dashed line. Damage region 18 can be formed byimplanting one or more isotopes of hydrogen into substrate 16; and canbe formed before or after forming other shown structures associated withsubstrate 16. Damage region 18 will ultimately be utilized for making aso-called “smart cut” within substrate 16. Damage region 18 can beformed within substrate 16 by, for example, a one-time dose withdeuterium to form the deuterium to an implant depth of from about 3,000angstroms to about 10,000 angstroms deep within substrate 16. Thedeuterium dose can be from about 3×10¹⁶ atoms/cm³ to about 7×10¹⁶atoms/cm³.

Diffusion regions 20 and 22 are formed within portion 12, and diffusionregions 24 and 26 are formed within portion 14. Diffusion regions 20,22, 24 and 26 can comprise n-type diffusion regions or p-type diffusionregions.

An insulative material 28 extends across an upper surface of substrate16. Insulative material 28 can comprise, for example, silicon dioxide.Another insulative material 30 is also formed across the upper surfaceof substrate 16. Insulative material 30 can comprise the same materialas insulative material 28, or can comprise a different material. Inparticular embodiments, both insulative material 28 and insulativematerial 30 will comprise silicon dioxide. Conductive projections 32 and34 are formed within portion 12, and conductive projections 36 and 38are formed within portion 14. Projections 32, 34, 36 and 38 cancomprise, for example, conductively-doped silicon, such as, for example,conductively-doped polycrystalline silicon. Projections 32, 34, 36, and38 electrically connect with diffusion regions 20, 22, 24 and 26,respectively. Projections 32, 34, 36 and 38 will ultimately beincorporated as storage nodes of capacitor constructions.

A dielectric material 40 is formed across projections 32, 34, 36 and 38.Dielectric material 40 can comprise, for example, one or more of silicondioxide and silicon nitride; and/or can comprise various high-Kdielectric materials, such as, for example, tantalum pentoxide, hafniumoxide or aluminum oxide.

A conductive mass 42 is formed over dielectric material 40. Conductivemass 42 can comprise, for example, conductively-doped silicon. A secondconductive mass 44 is formed over mass 42. Second conductive mass 44 cancomprise, for example, a silicide, and can enhance electrical conductionacross and within mass 42 in embodiments in which conductive mass 42comprises doped silicon. It is to be understood that the inventionencompasses other embodiments wherein second conductive mass 44 isomitted. Conductive mass 42 is ultimately incorporated as a cell platein capacitor constructions, and dielectric material 40 is ultimatelyincorporated into the capacitor constructions to separate the cell platefrom the storage nodes 32, 34, 36 and 38.

A bonding region 46 is shown formed over second conductive mass 44.Bonding region 46 typically comprises an oxide, such as, for example,silicon dioxide. Bonding region 46 can, however, comprise any materialsuitable for low temperature bonding (i.e., bonding at a temperaturebelow 550° C. Low temperature bonding is desired in order to avoiddiffusion of dopant beyond desired implant regions.

A silicon substrate 48 is shown bonded to bonding region 46. Substrate48 provides a “handle” for manipulating wafer 10 during subsequentprocessing. The bonding of substrate 48 to region 46 can be accomplishedby providing a first portion of oxide 46 associated with substrate 48and a second portion of oxide 46 associated with silicide 44, andsubsequently bonding the two oxide portions with one another by heatingthe oxide portions to a temperature of about 550° C. for a time of about30 minutes.

Referring to FIG. 2, wafer 10 is shown in an inverted orientationrelative to FIG. 1. The orientation of wafer 10 is inverted so thatsubsequent devices can be formed on substrate 16. Substrate 16 has beencleaved along defect region 18 (FIG. 1). Such cleavage can occurutilizing, for example, thermal processing and/or ultraviolet light.After the cleavage, substrate 16 is planarized to bring an illustratedupper surface of FIG. 2 down to a level of diffusion regions 20 and 22.Subsequently, trenches are formed within substrate 16 and filled withinsulative material to define isolation regions 50 adjacent thediffusion regions 20 and 22, as well as to form an isolation region 50between the diffusion regions 24 and 26. A suitable insulative materialfor isolation regions 50 is silicon dioxide.

Referring to FIG. 3, layers 52, 54 and 56 are formed over substrate 16,and in the shown embodiment form stacks over active areas of the cell.Layers 52, 54 and 56 can comprise, for example, silicon dioxide,conductively-doped silicon, and silicon nitride, respectively. Layer 54can comprise metal silicide and/or elemental metal in addition to, oralternatively to, conductively-doped silicon. Layers 52 and 56 can bereferred to as insulative material layers, and layer 54 can be referredto as a conductive material layer. In an exemplary embodiment, layer 52comprises silicon dioxide or high-k dielectric material, and has anappropriate thickness to produce an electrically equivalent thicknessrelative to SiO₂ of about 15 Å. Layer 54 comprises conductively-dopedpolycrystalline silicon, and has a thickness of about 300 angstroms.Also, layer 56 comprises silicon nitride, and has a thickness of about200 angstroms.

A pair of openings are formed through layers 52, 54 and 56 relative toportion 12, and such openings are filled with insulative material 58.Material 58 can comprise, for example, silicon dioxide. Also, a openingis formed relative to portion 14 and filled with insulative material 58.A misalignment-allowing patterning can be included, if desired.

Referring to FIG. 4, layer 56 is etched from over first portions 60 ofregion 12, while leaving some of layer 56 over a second portion 62 ofregion 12. The layer 56 remains over region 14 during the removal ofportions of layer 56 relative to region 12. In embodiments in whichlayer 56 comprises silicon nitride, a suitable etch can be accomplishedutilizing CF₄ and O₂. Prior to the etch, photolithographic processingcan be utilized to form a patterned photoresist (not shown) whichultimately is utilized for patterning layer 56 into the shownconfiguration.

Referring to FIG. 5, a conductive material 64 is formed over regions 12and 14. Conductive material 64 can comprise, for example,conductively-doped silicon, such as conductively-doped polycrystallinesilicon. Conductive material 64 can alternatively, or additionally,comprise W and/or WN. Conductive material 64 can alternatively, oradditionally, comprise metal silicide or elemental metal. Conductivematerial 64 can be formed to a thickness of, for example, from about 200Å to about 500 Å.

Conductive material 64 contacts conductive layer 54 at regions 60, butis separated from material 54 at the region 62 of portion 12. In theshown embodiment, conductive material 64 physically and electricallycontacts conductive material 54 at the region 60 of portion 12.

Conductive material 64 is separated from conductive material 54 acrossan entirety of portion 14. Specifically, insulative material 56 withinportion 14 physically and electrically separates conductive material 64from conductive material 54.

An insulative material 66 is formed over conductive material 64.Insulative material 66 can comprise, for example, silicon dioxide, andcan be formed to a thickness of, for example, from about 100 Å to about300 Å.

A patterned photoresist layer 68 is formed over portions 12 and 14, andspecifically is formed over insulative material 66. Photoresist layer 68can be patterned by, for example, photolithographic processing. Thepatterned photoresist 68 has openings 70, 72, 74, 76, 78 and 80extending therethrough.

Referring to FIG. 6, openings 70, 72, 74, 76, 78 and 80 are extendedthrough materials 66 and 64, to terminate at insulative materials 56 and58.

Referring to FIG. 7, openings 72, 76 and 80 are extended to substrate 16(or at least to proximate substrate 16), while openings 70, 74 and 78are not significantly extended. In a preferred embodiment in whichmaterial 56 comprises silicon nitride, material 54 comprises, orconsists essentially of conductively-doped silicon, and blocks 58comprise silicon dioxide; a suitable etch is an etch selective forsilicon nitride and conductively-doped silicon relative to silicondioxide.

It is noted that the shown etch has penetrated through the thin silicondioxide layer 52. Such can be accomplished by utilizing an etch which isnot entirely selective for silicon dioxide material relative to siliconnitride and conductively-doped silicon. The etch will then remove someof conductive blocks 58, and will penetrate silicon dioxide layer 52.However, it is to be understood that the invention encompasses otherembodiments (not shown) wherein the etch only penetrates through siliconnitride layer 56 and conductively-doped silicon layer 54, and does notpenetrate through silicon dioxide layer 52.

After openings 72, 76 and 80 are extended, a dopant is implanted intothe openings to form conductively-doped diffusion regions 84, 86 and 88.Diffusion regions 84, 86 and 88 are shallower than adjacent diffusionregions, and can be ultra-shallow. Diffusion regions 84, 86 and 88 cancomprise, for example, n-type doped regions. The diffusion regions areillustrated extending only partially into substrate 16, but it is to beunderstood that the invention encompasses other embodiments (not shown)wherein the diffusion regions are extended entirely across (through)substrate 16.

Referring to FIG. 8, photoresist 68 (FIG. 7) is removed, andsubsequently an insulative mass 90 is formed over portions 12 and 14.Mass 90 fills openings 72, 76 and 80 (FIG. 7), as well as openings 70,74 and 78 (FIG. 7). Mass 90 is planarized utilizing, for example,chemical-mechanical polishing. Mass 90 can comprise, for example,silicon dioxide. After mass 90 is planarized, a photoresist mask 92 isformed over portions 12 and 14. Mask 92 is patterned over portion 14utilizing, for example, photolithographic techniques. The patterned mask92 over portion 14 has openings 94, 96 and 98 extending therethrough.

Referring to FIG. 9, openings 94, 96 and 98 are extended through layers56, 64 and 66 to expose a surface of conductive layer 54. Photoresist 92(FIG. 8) is subsequently removed, and spacers 100 are formed withinopenings 94, 96 and 98 to narrow the openings. Spacers 100 cover edgesof conductive material 64 that would otherwise be exposed within theopenings. Spacers 100 can be formed by, for example, depositing asuitable insulative material (such as, for example, silicon dioxide orsilicon nitride), and subsequently exposing the insulative material toan anisotropic etch to pattern the material into the shown spacers.

Referring to FIG. 10, a conductive material 102 and an insulativematerial 104 are formed over portions 12 and 14. Electrically conductivematerial 102 can comprise, for example, conductively-doped polysiliconand electrically insulative material 104 can comprise, for example,silicon dioxide or silicon nitride. Conductive material 102 extendswithin openings 94, 96 and 98 to form electrical interconnects whichelectrically contact conductive material 54. Conductive material 102 canbe considered to define a conductive line extending across portion 14and electrically connected to conductive material 54 throughinterconnects that extend within openings 94, 96 and 98. In the shownembodiment, the interconnects are formed simultaneously with theformation of the conductive line 102 and comprise the same material asconductive line 102. However, it is to be understood that the inventionencompasses other embodiments (not shown) wherein the conductiveinterconnects are formed within openings 94, 96 and 98 prior toformation of conductive line 102, and wherein the conductiveinterconnects comprise a different material than conductive line 102.

Portions 12 and 14 comprise transistor/capacitor pairs that can beconsidered elements of DRAM cells. For instance, portion 12 comprises aregion of conductive material 54 extending between conductively-dopedregions 20 and 84 that can be considered as a first transistor gate 110.Specifically, conductive material 54 can gatedly connectconductively-doped regions 20 and 84 through a channel region 112defined beneath conductive layer 54 and within semiconductive materialsubstrate 16. Such channel region can be appropriately doped prior toformation of oxide layer 52 at, for example, the processing step shownin FIG. 2. Conductive material 32 can be considered to comprise astorage node of a capacitor construction 114, and transistor 110 can beconsidered to electrically and gatedly connect capacitor construction 32with conductively-doped region 84.

A second transistor gate 116 is defined by a region of conductivematerial 54 extending between diffusion regions 22 and 84, and suchcomprises a channel region 118 therebeneath. Transistor gate 116electrically and gatedly connects capacitor 34 with a node locationdefined by diffusion region 84.

Referring to portion 14, such comprises a transistor gate defined by aregion of conductive material 54 extending between diffusion regions 24and 86, and which is labeled as transistor gate 120. Transistor gate 120comprises a channel region 122 therebeneath. Also, a transistor gate 124is defined by a region of conductive material 54 extending betweendiffusion regions 26 and 88, and such has a channel region 126 extendingthereunder. Transistor gate 120 gatedly connects a capacitor comprisingstorage node 36 with a node location defined by conductively-dopedregion 86; and transistor 124 gatedly connects a capacitor comprisingstorage node 38 with a node location defined by diffusion region 88.

In particular aspects of the invention, conductive layer 64 can beconsidered a first conductive line, and conductive layer 102 can beconsidered a second conductive line. Conductive line 64 electricallyconnects with transistor gates defined by material 54 over region 12,but does not electrically connect with conductive material 54 overregion 14. Instead, line 64 is separated from conductive material 54over an entirety of region 14 by insulative material 56. In contrast,the conductive line defined by material 102 electrically connects withconductive material 54 and any transistor gates defined thereby overregion 14, but does not electrically connect with material 54 overregion 12. Instead, the conductive line defined by material 102 isseparated from conductive material 54 over region 12 by at least theinsulative materials 66 and 90.

Ultimately, electrical connections can be formed through materials 104,102 and 90 to diffusion regions 84, 86 and 88 to allow bitlineconnections to such diffusion regions. Accordingly, DRAM arrays can bedefined wherein conductive material 54 defines a wordline havingtransistor gates comprised thereby, and bitline interconnections areformed to node locations 84, 86 and 88. FIGS. 11-15 illustrate anexemplary method of forming bitline interconnections to node locations84, 86 and 88.

Referring to FIG. 11, a patterned mask 300 is formed over regions 12 and14. In the shown embodiment, mask 300 includes a first component 302comprising silicon and nitrogen (with an exemplary composition of thefirst component being silicon nitride), and a second component 304comprising photoresist. Openings 310, 312, 314, 316, 318 and 320 aredefined by patterned mask 300.

Referring to FIG. 12 openings 310, 312, 314, 316, 318 and 320 areextended through layers 102 and 104. Also, photoresist component 304(FIG. 11) of mask 300 (FIG. 11) is removed. The openings 310, 312, 314,316, 318 and 320 are preferably aligned with blocks of material 90, butit is to be understood that some misalignment can occur.

Referring to FIG. 13, spacers 330 are formed within openings 310, 312,314, 316, 318 and 320; and component 302 (FIG. 12) of mask 300 (FIG. 11)is removed. Spacers 330 comprise electrically insulative material, andcan comprise, for example, silicon dioxide or silicon nitride. Afterformation of spacers 330 and removal of component 302, an electricallyinsulative material 332 is formed over regions 12 and 14 and withinopenings 310, 312, 314, 316, 318 and 320. Material 332 can comprise, forexample, silicon dioxide.

Referring to FIG. 14, a patterned mask 340 is formed over material 332.Mask 340 can comprise, for example, photoresist. Mask 340 definesopenings 350, 352 and 354; and such openings are extended substantiallyto diffusion regions 84, 86 and 88, respectively. The openings to thesource/drain regions are described above as being formed “substantially”to the source/drain regions to indicate that the opening extends closeenough to the source/drain regions to enable a conductive electricalconnection to extend from the source/drain regions to a conductivematerial formed within the openings. Such can be accomplished byextending the openings entirely to the doped source/drain regions, or byextending the openings to only near the source/drain regions.

Referring to FIG. 15, mask 340 (FIG. 14) is removed; and bitlineinterconnections 130, 131 and 133 are formed in openings 350, 352 and350 (FIG. 14), respectively. The interconnections include suitableconductive materials to establish conductive interconnects. In the shownembodiment, two conductive materials are utilized for theinterconnections. The first of the conductive materials is labeled as134, and the second conductive material is labeled as 136. Material 134can comprise, for example, titanium nitride or tungsten nitride; andmaterial 136 can comprise, for example, one or both of elementaltitanium and elemental tungsten. A silicide layer (not shown) can beformed at interfaces of the diffusion regions and conductive material134.

A bitline (or digitline) 400 is shown formed over regions 12 and 14.Bitline 400 can be a continuous bitline extending over both of regions12 and 14, or can comprise a separate bitline over region 12 relative tothat over region 14. The conductive interconnects 130, 131 and 133 areshown making bitline interconnections 140, 160 and 170, respectively.

A simplified diagrammatic view of regions 12 and 14 is provided in FIG.16 to illustrate various aspects of the present invention. FIG. 16illustrates portion 14 expanded to encompass a third storage node 150,and an additional diffusion region 152.

The simplified diagram of FIG. 16 shows that conductive layer 54 formstransistor gates over portions 12 and 14. The diagram of FIG. 16 furthershows that the transistor gates over portion 12 are electricallyconnected with a conductive line comprising layer 64, while thetransistor gates over portion 14 are electrically connected with aconductive line comprising material 102. In a sense, conductive material54 can be considered to define wordlines which spread over storage nodejunctions, and which are wider than an actual access gate length.Actually, conductive material 54 comprises portions of the wordlines,and the remaining conductive portions of the wordlines are defined byconductive materials 64 and 102. Materials 64 and 102 effectivelypiggyback over one another, but define two distinct wordlines which canbe utilized for addressing the circuitry over regions 12 and 14. The useof two wordlines can allow unique memory addressing of the transistorsassociated with region 12 versus those associated with region 14.

It is noted that regions 12 and 14 can alternate with respect to oneanother across a DRAM array, and further that the wordline connectionshown with respect to region 14, although different in symmetry than thewordline connections shown with respect to region 12, can have a verysimilar resistance to those of region 12. Such may be due to the topconductive material 102 having about a common influence over regions 12and 14, even though it does not directly connect with conductivematerial 54 over region 12. Processing of the present invention can berelatively simple, and can utilize less masks than prior art approachesfor forming DRAM cells. Although the diagram of FIG. 12 shows the stackof layers 54, 64 and 102 over node 150 to have an electrical connectionbetween layers 54 and 102, it is to be understood that the stack couldalternatively have the electrical connection between layers 54 and 64(i.e., could have the construction of the stacks associated withfragment 12, rather than the construction of the other stacks associatedwith fragment 14).

FIG. 17 is a top view of wafer fragment 10 illustrating exemplaryarchitecture which can be utilized with the methodology of the presentinvention. A series of bitlines 140, 160, 180 and 200 are illustratedextending longitudinally across the page, and wordlines 220 and 222 areillustrated extending laterally across the page. Wordlines 220 and 222have interconnections 224 and 226, respectively, which extend out of thepage. The interconnections can be connected to some conductive straps(not shown) which electrically interconnect the shown isolated portionsof regions 222 with one another, and to other conductive straps (notshown) which electrically interconnect the shown isolated regions ofportions 220 with one another.

Wordline region 220 comprises the connections shown previously forregions 12 (i.e. bottom connections), and wordline region 222 comprisesthe connections described previously with reference to portion 14 (i.e.the top connections). The architecture of FIG. 13 can be a true 6F²architecture. Specifically, a distance across a bitline (for example,bitline 160) can be 2F to define a width of a cell, and a length of thecell can be 3F. Accordingly, the area of the cell can be 6F².

In compliance with the statute, the invention has been described inlanguage more or less specific as to structural and methodical features.It is to be understood, however, that the invention is not limited tothe specific features shown and described, since the means hereindisclosed comprise preferred forms of putting the invention into effect.The invention is, therefore, claimed in any of its forms ormodifications within the proper scope of the appended claimsappropriately interpreted in accordance with the doctrine ofequivalents.

1. An array of memory cells comprising: a set of transistor gates, theset of transistor gates being defined to include a first subset oftransistor gates and a second subset of transistor gates; a first wordline over the set of transistor gates and electrically connected to thefirst subset of transistor gates; a second word line over the first wordline and electrically connected to the second subset of transistorgates; openings extending through the first word line and to the secondsubset of transistor gates; and wherein the first word line does notelectrically connect with the second subset of transistor gates and thesecond word line does not electrically connect with the first subset oftransistor gates.
 2. The array of claim 1 wherein the second word lineis over the set of transistor gates.
 3. The array of claim 2 wherein thefirst word line is physically against the first subset of transistorgates, and further comprises an insulative material layer over thesecond subset of transistor gates; the insulative material layerphysically and electrically separating the second subset of transistorgates from the first word line.
 4. The array of claim 1 furthercomprising: openings extending through the first word line and to thesecond subset of transistor gates; sidewall spacers within the openingsand narrowing the openings; and conductive material within the openings,the conductive material electrically connecting the second word line tothe second subset of transistor gates.
 5. The array of claim 4 whereinthe conductive material comprises conductively-doped silicon.
 6. Thearray of claim 1 wherein the first and second word lines compriseconductively-doped silicon.
 7. The array of claim 1 wherein the firstword line is physically against the first subset of transistor gates,and further comprises an insulative material layer over the secondsubset of transistor gates; the insulative material layer physically andelectrically separating the second subset of transistor gates from thefirst word line.
 8. The array of claim 7 wherein the insulative materiallayer comprises silicon nitride.
 9. The array of claim 1 furthercomprising: a semiconductive material under the first and second subsetof transistor gates and over capacitor constructions; conductively dopedsource/drain regions within the semiconductive material, thesource/drain regions being proximate at least some of the first andsecond subset of transistor gates; openings extending through the firstand second word lines and to the source/drain regions; and bitlineinterconnections within the openings and electrically connected throughthe first and second subset of transistor gates to the capacitorconstructions.
 10. An array of memory cells comprising: a set oftransistor gates, the set of transistor pates being defined to include afirst subset of transistor gates and a second subset of transistorgates; a first word line over the set of transistor pates andelectrically connected to the first subset of transistor gates; a secondword line over the first word line and electrically connected to thesecond subset of transistor gates, the second word line being directlyover the first word line; and wherein the first word line does notelectrically connect with the second subset of transistor gates and thesecond word line does not electrically connect with the first subset oftransistor gates.
 11. An array of memory cells comprising: a set oftransistor gates, the set of transistor gates being defined to include afirst subset of transistor gates and a second subset of transistorgates; a first word line over the set of transistor gates andelectrically connected to the first subset of transistor gates; a secondword line over the set of transistors and the first word line andelectrically connected to the second subset of transistor gates; andopenings extending through the first word line and to the second subsetof transistor gates; sidewall spacers within the openings and narrowingthe openings; and conductive material within the openings, theconductive material electrically connecting the second word line to thesecond subset of transistor gates; wherein the first word line does notelectrically connect with the second subset of transistor gates and thesecond word line does not electrically connect with the first subset oftransistor gates.
 12. The array of claim 11 wherein the conductivematerial comprises conductively-doped silicon.
 13. An array of memorycells comprising: a set of transistor gates, the set of transistor gatesbeing defined to include a first subset of transistor gates and a secondsubset of transistor gates; a first word line over the set of transistorgates and electrically connected to the first subset of transistorgates; a second word line over the set of transistor gates and the firstword line and electrically connected to the second subset of transistorgates; and wherein the first and second word lines compriseconductively-doped silicon, and the first word line does notelectrically connect with the second subset of transistor gates and thesecond word line does not electrically connect with the first subset oftransistor gates.
 14. An array of memory cells comprising: a set oftransistor gates, the set of transistor gates being defined to include afirst subset of transistor gates and a second subset of transistorgates; a first word line over the set of transistor gates andelectrically connected to the first subset of transistor gates; a secondword line over the set of transistor gates and the first word line andelectrically connected to the second subset of transistor gates; andwherein the first word line does not electrically connect with thesecond subset of transistor gates and the second word line does notelectrically connect with the first subset of transistor gates; andwherein the first word line is physically against the first subset oftransistor gates, and further comprises an insulative material layerover the second subset of transistor gates; the insulative materiallayer physically and electrically separating the second subset oftransistor gates from the first word line, and the insulative materiallayer comprises silicon nitride.
 15. An array of memory cellscomprising: a set of transistor gates, the set of transistor gates beingdefined to include a first subset of transistor gates and a secondsubset of transistor gates; a first word line over the set of transistorgates and electrically connected to the first subset of transistorgates; a second word line over the set of transistor gates and the firstword line and electrically connected to the second subset of transistorgates; a semiconductive material under the first and second subset oftransistor gates and over capacitor constructions; conductively dopedsource/drain regions within the semiconductive material, thesource/drain regions being proximate at least some of the first andsecond subset of transistor gates; openings extending through the firstand second word lines and to the source/drain regions; and bitlineinterconnections within the openings and electrically connected throughthe first and second subset of transistor gates to the capacitorconstructions; and wherein the first word line does not electricallyconnect with the second subset of transistor gates and the second wordline does not electrically connect with the first subset of transistorgates.
 16. An array of memory cells comprising: a set of transistorgates, the set of transistor gates defining a first subset of transistorgates and a second subset of transistor gates; a first conductive lineover the set of transistor gates and electrically connected to the firstsubset of transistor gates; and a second conductive line between thefirst conductive line and the set of transistor gates, the secondconductive line being electrically connected to the second subset oftransistor gates; wherein openings extend through the first conductiveline and to the second subset of transistor gates.
 17. The array ofclaim 16 wherein the first conductive line is directly over the secondconductive line.
 18. An array of memory cells comprising: a set oftransistor gates, the set of transistor gates defining a first subset oftransistor gates and a second subset of transistor gates; a firstconductive line over the set of transistor gates and electricallyconnected to the first subset of transistor gates; and a secondconductive line between the first conductive line and the set oftransistor gates, the second conductive line being electricallyconnected to the second subset of transistor gates, and the first andsecond conductive lines comprise conductively-doped silicon.
 19. Anarray of memory cells comprising: a set of transistor gates, the set oftransistor gates defining a first subset of transistor gates and asecond subset of transistor gates; a first conductive line over the setof transistor gates and electrically connected to the first subset oftransistor gates; a second conductive line between the first conductiveline and the set of transistor gates, the second conductive line beingelectrically connected to the second subset of transistor gates; asemiconductive material under the set of transistor gates and overcapacitor constructions; conductively doped source/drain regions withinthe semiconductive material, the source/drain regions being proximate atleast some of the set of transistor gates; openings extending throughthe first and second conductive lines and to the source/drain regions;and bitline interconnections within the openings and electricallyconnected through the set of transistor gates to the capacitorconstructions.